This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The aim of this study is to compare alternative therapy(hydroxyurea treatment with repeated phlebotomy) with standard therapy (monthly erythrocyte transfusions with daily iron chelation) for the prevention of secondary stroke and reduction of transfusional iron overload in pediatric subjects with SCA and previous stroke, as well as to compare alternative therapy to standard therapy for effects on quality of life, the frequency of non-stroke neurological events and other sickle cell related events, and on growth and development.